Method of manufacturing a semiconductor device in which a surface of a semiconductor body is provided with mutually-insulated aluminum tracks

Abstract

A method of manufacturing a semiconductor device whereby on a surface (1) of a semiconductor body (2) a layer comprising aluminum (3) is deposited, in which conductor tracks (4) are etched, between which then an insulating aluminum compound (6) is provided in that a layer of such a material (7) is deposited, which layer is then removed down to the conductor tracks (4) by a bulk reducing treatment, upon which an insulating layer (11) is deposited into which contact windows (13, 14) are etched down to the layer comprising aluminum (4) for local contacting of the conductor tracks (4). The conductor tracks (4) are provided with a top layer (8) before the deposition of the insulating aluminum compound, and the aluminum compound is removed again down to the top layer (8) after the deposition by means of a polishing treatment which is practically incapable of removing the top layer (8). Mutually insulated conductor tracks (4) can be made in this manner which are suitable for use in integrated circuits with a very high integration density (VLSI).

We claim: 
     
       1. A method of manufacturing a semiconductor device whereby a layer comprising aluminium is deposited on a surface of a semiconductor body, into which layer conductor tracks are etched, between which tracks an insulating aluminium compound is provided by a layer of such a material being deposited and subsequently removed by a bulk reducing treatment down to the conductor tracks, after which a layer of insulating material is deposited in which contact windows are etched down to the layer comprising aluminium for local contacting of the conductor tracks, characterized in that the conductor tracks are provided with a top layer before the deposition of the layer of the insulating aluminium compound, in that the top layer is provided of the same material as said layer of insulating material, and in that after said deposition of the insulating aluminium compound a percentage of the insulating aluminium compound is removed to expose said top layer by a polishing treatment during which a percentage of the top layer between zero percent and a percentage less than said percentage of the insulating aluminium compound is removed. 
     
     
       2. A method as claimed in claim 1, characterized in that the layer comprising aluminium is provided with the top layer before the conductor tracks are formed therein, and the conductor tracks are formed both in the layer comprising aluminium and in the top layer. 
     
     
       3. A method as claimed in claim 1, characterized in that the top layer comprises silicon oxide. 
     
     
       4. A method as claimed in claim 3, characterized in that the top layer of silicon oxide has a thickness of 10 to 100 nm. 
     
     
       5. A method as claimed in claim 1, characterized in that the polishing treatment is carried out with a slurry comprising a silicon oxide powder which is brought to a pH value of 3 to 5 by means of an acid. 
     
     
       6. A method as claimed in claim 5, characterized in that the acid with which the slurry is brought to the desired pH value is phosphoric acid.